Trap-pic signal



3 Sheets-Sheet 1 ,J. C. BUTTERFIELD TRAFFIC SIGNAL Filed Sept. 28 9 1926.

Sept. 28 1926. 1,6015428" J. c. BUTTERFIELD TRAFFIC SIGNAL Filed July 25. 1921 3 Sheets-Sheet 2 z 565.0 Sla' w77 75 (3 Gttozmg -tll Patented Sept. 28, 1926.

UNITED STATES JOHN c. BUTTERFIELD, or BELMOND, rowA.

TRAFFIC src-NAL.

'Application filed July 25, 1921. Serial No. 487,506.

v This invention relates 'to signals of the character employed at street intersections for automatically controlling the flow of trafiic past the intersection, the signal working at predetermined intervals to alternately direct the traffic yon intersecting streets across the intersection.

The signal is preferably positioned in the center of the intersecting streets, but can be placed on one or more of the corners of the intersection, if desired.

An object of the invention is to construct a lsignal that can be used 'to good advantage in the middlev of the intersection.

` Another "object is to eliminate mechanical faults of Vconstruction so as to obviate breaking down of the signal when being used.

`Another object is to make provision for relative movement. between the semaphore and its standard so that if the semaphore be struck by a vehicle it will rotate and not be broken or bent.

Another object is to make provisin for r swinging the semaphore into vertical position when it is not desired to have the signal in operation.

Another object is to provide timing mechanism reliable in operation so vas to effectively and simultaneously control a series of fthe signaling mechanisms placed at different street intersections.

Other objects and advantages will appear inthe subjoined detailed description.

The accompanying drawings illustrate the invention:

Figure 1 is a side elevation of a traffic signal constructed in accordance with the provisions `of this inventionthe semaphore being shown in solid lines in positionfor directing the traffic in a direction parallel with the plane of the drawing, broken lines indicating the semaphore in position when it is out of use.

Figure 2 is an enlarged side elevation of the upper portion of the signal shown in Figure l, a portion of the lend of the semaphore being broken away tod-isclose a spring latch that would otherwise be partly hidden from view.

Figure '3 is an elevationsimilar to Figure 2, the parts being mainly in vertical midsection.

Figure 3 is an elevation of the lower end 0f the sleeve from the right of Figure 2.

line indicated by rfi-a, Figure l, omitting the bell and transformer.

Figure 7 "is an enlarged plan view of the timing mechanism.

Figure 8 is a front elevation of Figure 7,

omitting the motor, dotted lines indicating l one of the electric contacts in open position.

Figure 9 is an end elevation from the left of Figure 8, dotted lines indicating l'two Aof the contacts inthe position they occup57 corresponding with the dotted position of one of them in Figure 8.

Figure 10 is an enlarged detail of the switch arm-operating ratchet device.

Figure l1 is a diagram indicating the electrical connections for a trafiic signal system, two signaling mechanisms and one timing mechanism being indicated.

Figure l2 is a fragmental vertical sec-tion of a street showing the wires, connecting the signaling and 'timing mechanism, embedded in the 'material of which the street surface is constructed.

The signaling mechanism will first ybe de'- scribed: There is provided a suitable housing l fastened vby screws 2 to a base or pedestal 3 made of cast iron or other suitable Vinaterial so as to securely hold the housing l in position in the 'center of intersecting streets or on one of the corners ofthe intersection or wherever else it may be desired to position the signaling mechanism. If desired, the base 3 may be embedded in the street or sidewalk, but this is not necessary. The base `3 weighs 'several hundred pounds, so that the housing cannot be moved without the exertion of a considerable force. The opposite sides of the housing l are provided with doors l having perforated ears 5 at their. lower ends adapted, when the doors are closed, to register with perforated ears 6 mounted on the base 3 so that padlocks may be used to secure the ears 5, 6 to each other to prevent opening of the doors t by unauthorized persons.

The bottom of the housing l is indicated at? and mounted thereon is a motor 8 having a shaft 9. The shaft 9 is provided near one end with a collar 10 and said shaft is also provided with a friction clutch, one

member 11 of the clutch being fastened by a screw 12 to the shaft 9 and the other member 13 of the clutch being loose on said shaft. Between the clutch member 13 and collar is interposed a coil spring 14 adapted to press the clutch member 13 into trictional engagement with the clutch member 11.

The clutch member 13 constitutes a drum and fastened thereto by a screw 15 is one end of a chain or other iiexible line 16. The opposite end ot' the chain 16 is secured by a screw'l'i to the bottom 7. The chain 16 is also secured between its ends, as indicated at 18, to an arm 19 ot an oscillatory member, indicated in general by the character 20. 'The arm 19 is normally held in a direction away from the clutch 12, 13, by a coil spring 2l secured atV one end to the arm 19 and at its oppositelend by a bracket 22 to one ot the side walls of the housing; 1. lVhen themotor 8 operates it turns the` shaft 9 in a direction toV wind the chain 16 on the drum `13 so as to turn the member 2O in the direction ot the arrow a in Fig-ure 6. Y lWhen the slack in thel chain 16e between the arm 19 and the screw 17, has been taken up by the turning movement of the drum 13 shaft 23.

' shaft 23.

The shaft 23 is provided with a tour'teeth ratchet wheel 25 engaged by a pawl 26, the pawl and ratchet construction being' such that when the motor operates to turn the member 2O in the direction ot the arrow ct thepawl 26 engages the ratchet wheel and turns said wheel, which thus rotates the Then the current is cut oit from the motor 8, the spring 21 functions to retract or turn the member 2O in a direction opposite to that indicated by the arrow whereupon the pawl 26 will slip over the teeth of the ratchet wheel 25. so as not to turn the shaft 3 in a reverse direction.

v'rlhe'ratchet wheel 25 is yielding'ly held against turning by a flat` spring 27, the ratchet wheel having four sides at right angles to one another so that the spring 27 will successivelyengage the sides ott said ratchet wheel to hold it in as many different positions ninety degrees of circle measure apart. It will be clear from this that the ratchet wheel 25 is given a quarter turn each time the motor operates. The spring` Inserted l 2? is mounted on the housingbottom 'l'. lilhen the ratchet wheel 25 has been turned to a position a tritie more than :forty-live de grecs trom the position shown .in Figure (l, the spring` 27 aids in turninr` said ratchet wheel.

The pawl and ratchet device described above will produce the desired intermittent quarter turningot the shalt 23, but it is desirable that the shaft 23 be held against turning independent et the oscillatory nember in the direction indicated by the arrow e, for a reason that will be made clear hereinafter. To prevent such independent turning, l provide a second pawl 23 operating oppositely to the pawl 2G and both pawls 2G, 28 are normally held in engagement with the ratchet wheel by a coil spring 29 tastened at its opposite end to the pawls, which are rtspectiveiy pivoted at 30 to the member 20.

l provide suitable means to retractthe rawl 2S troni engagement with the ratchet wheel 25 when the member 2O is turned by operation ot the motor 3. Such means7 in the instance shown in the drawings, einA body a coil spring` 31 fastened at one end to the pawl. 23 and at its opposite end to the adjacent side ot the housing.: 1. lVhen the member 2O is in the retracted position shown in Figure (l oi the drawings the springr 3l will be under no tension. Them however. the member 2() is turned in the direction olf the arrow e, the spring; 31 will be lengthened sutiiciently to put it under tension. and such tension operates to retract the pawl 23. It is necessary to retract the pawl 23 in this manner, so that on the return nierement of the member 20, due to the pull et the spring 2l, the pawl 23 will not engage the ratchet wheel 25 and thus turn the shaft in a reverse direction to that elleeted by the pawl 25.

Mounted on the upper end ot the shaft 23 is a semaphore 32 and, though said semaphore may be iixed to said shatt it is preterable to malte provision tor turning' ot the semaphore about the airis ot the shatt 23 when said shaft 23 is held stationary.y as ei:- plained above, that a vehicle accidentally striking` the semaphore will simply c: o the semaphore to turn on the sha'l` 23 and thus not break or injure the signalingT nicchanism. rl'he construction which l employ at present tor thus mounting the semaphore is as follows: The semaphore 32 hollow and is provided with a vertical sleeve 313 llt-- ting around the upper end ot the shatt 23. rllhe lower end ot the sleeve 33 is ot irrealin lar contour to form a cani 34 which rests upon a roller 35 n'iounted on a screw 3G projecting trom tl e shaft 23. lit the soma* phore 32 be turned relative to the sha tt 23 to the right or lett in Figure 25 the ham 34 will ride up on the roller 35 against the lll) vorce 'of gravity, and gravity will, therefore, tend to return the semaphore to normal position when it is released. This tendei'iey to return to normal may be emphasited by a suitable coil spring 37 `fastenedt its 4upper end vby a stud 38 to the semaphore and Aat its lower end by 'a stud 39 to the shaft 23. This spring 37 pulls downwardly on the semaphore 32 so as to tent to move. the cam 34 into the position shown in FigureQ. y

JWhen it is not desired to have the sigg nal operate, it is preferable to swing the semaphore into vertical position so that it will be non-indicative ot trahie flow past the intersection, and also so that there will be less danger of a vpassing vehicle striking; the ends of the semaphore. For this reason., 'the semaphore 32 is pivoted to the sleeve `33, the pivot this instance beine formed by the stud 38. It is now clear.' that the semaphore 32 may be swuno into the verti l position indicated in bro-en lines in ure 1. When thus swung into vertical positiony'the semaphore 32 may be yieldingly held by a resilient hook or latch e() fastened near one end of the semaphore and adapted toV be sprungv suliiciently by the shaft 23, when the semaphore is swung into -the vertical position indicatedvin broken lines c, Figure l, to grip the shaft between the hook and the inside face oit' the semaphore.

lf the semaphore 82 be thus pivoted to the sleeve 33, spaced ears il will be provided on one face of the semaphore to engage on opposite sides of the spring 37 when the semaphore is in thehorizontal position. The notch formed by the ears il is positioned substantially in vertical alinement with the studi-58. Vhe'n the semaphore S2. is t'orcibly turned in its vertical path of motion to the "signalingr and non-signaling positions7 the spring '37 will readily snap in and out of the n'fotch between the ears 4l. Position-ed on theinner face of one side of the hou ing is an electric bell 42 and also a suitable bell ringing' transformer 43.

The timing mechanism will now ,be de scribed; There is provided a suitable base 44- which form the bottom ot' 'a clase or housing that is not lshown in full Vand that 'may be employed for housingthe timing mechanism, or, if desired, the timing mechanisni maybe monnte'd in the housing l ot the signaling mechanism. Mounted on the base 44 lan electric motor 4.5 having a hori- Vz'ontal shaft Litpwhich vis coupled at t7 to a worin 'shaft 48 provided with a worm 4i). The worm 49 is in mesh with a. worm gear 50 mounted on a transverse horizontal shalt which is also provided with a spur pinion '52 in mesh with a spur gear The shalt '48 is journaled in a bearing 54 and is provided with a collar' 55 to take up end thrust. The shaft 5l is journaled in bearings 56.

al toothed wheel 62 mounted on one end ot)v a shaft Operation of the eccentric eflects step by step rotation ot the wheel 62, which is thus turned comparatively slowly. Also engaging the toothed wheel 62 is a 1check pawl 64 which is pivotally inolnitecL at 65. Both. detent 6l and pawl (Sii are yield ingly held in engagement with the toothed wheel 62 by a coil spring 66 fastened at its opposite ends to said detent and pawl.

The opposite end ot' the shaft't 63 is provided with a switch arm contact 67 adapted once in each revolution ol the shaft 63, to 'engage an electric switch Contact 68 which is pivotally mounted at 69 on a bracket 7 0 suitably insulated at 7l. The contact 68 is normally held in the path ot tra-vel otl the Contact 67 by a coil spring` 72 `fastened at one end to the upper end ot the contact 68 and at its opposite end to the bracket 76. The pat-h o't` movement o1"- the Contact 67 is substantially at right angles to the path of movement of the contact 68;

The contact arm 67 has another function than closing an electric circuit andnzheretore, it is adapted Ionce in each revolution to engage one of four arms 73 tast on the 7e which is journaled in bearings 75, 76. These arms 73 are at rightI angles to one another and project from a tour-sided hnb 77 whichconstitutes a cam. ln contact with the cam 77 is a spring arm 76 fastened at its lower end to the base and carrying;` an electric contact 79 at its upper end. As the cam 77 turns it moves the contact 7S) into engagement with a stationary electric contact. 80 mounted on the upper end ot a standard 8l which is fastened to the base t. Because of its square cross section., the cam 77 causes engagement ont' the contacts 79, 8O fourv times to each revolution ot the shaft 7e, or. in other words, the electric circuit controlled by the contacts 79, 8O is closed once to each quarter revolution ot the 'shaft 741 'Ihespringg arm 78 permits but a quarter turn of the shaft 71teaeh time that any one of the arms 73 is engaged by the Contact arm 67. Thus it is clear that the circuit controlled by the contacts 67, 66 and also the circuit controlled by the contacts 79. 60 are closed once in each revol .tion of the shaft 63. lt is also clear that contacts 67, 68 engage slightly before he contacts 7 9, 80, and that there is a sligrnt interval off time between the engagement et the two sets ot contacts. Y

' A switch is provided for opening and closingthe bell ringing circuit and said switch comprises a Stationary contact 82 mounted on the housing bottom 7. Adapted to engage the contact 82 is a resilient contact 83 which is fastened at one end to the housing bottom 7 and is provided with an eye 84C pivotally engaged by the lower end of an. operating rod 85, rlhe upper end oit the rod 85 passes `through a hole S0 in the top t3? ot the housing and is pivotally connected to one end ot a lever 88 which is fulcrumed at 89 on a standard 00 mounted on the top 87. lillhen the free cud of the lever is depressed it causes the contact 83 to be raised from the contact 82 so as to open the circuit in which said contacts are included.

On the housing top 8?" are mounted a pair of lamp sockets 91 holding); incandescent lamps 92, preterably ol a ruby or 'ed color.

The various electrical connections may be made as shown dizu inn'iatically in lig'ire 11, and in said heur l have shown two lik signaling mechanisms controlled by one timing; mechanism. Th se electrical connections will now be described: ltlach bell 4t2 is ccnnected by wires 93, 94.- to one ot' the coils ot the associated transformer ll, and one end of the other coil of each transloiv er it ennected by a wire 95 to the associated switch contact 83. rEhe other switch contacts 82 are connected to wires 9G w nch are grounded at 97. rlhe transformer 3 are connected by a wire 98 which, in turn, is connected by a` wire 99 to the contact arm 00. The con tact 07 is connected by a wire 100 to one ot the current mains 101. rlhus when the switch 82, 83 is closed and the contacts 07, 68 are engaged, the bells ft2 will ring.

The other electric current supply main 102 is grounded7 as indicated at 103. rhe'motor 4:5 is connected by a wire 104tto a switch conta ,t 105 adapted to be engaged by a switch contact connected by a wire 107 to the main 101. Thus when the switch 105, 100 is closed, the motor l5 will operate.

The standard 81 is connected by afwire 108 tothe wire 100 and the sprinn arm 78 is connected by a wire 109 and branches 110,

111 to the motors 8. The motors 8 are connected to wires 112. grounded indicated at 118, .nus when the contacts 79. 80 are closed the motors 8 will be energized.

The lamp sockets 91 ot each pair or" lamps 02 are connected together by a wire 11st which is grounded as indicated at 115. Vlhe lamp sockets 91 are also connected. together by wires 116 which are connected by a wire 117, and the wire 117 is connected to a wire 118 that is connected to a switch contact 119. rlhe associated switch Contact 120 is connected by a wire 121 to the main 101. llilhen the switch contacts 11.9, 120, are closed, the lamps 92 are supplied with electric current.

From the foregoing. it is seen that duplicate signaling` mechanisms are to be placed at different street intersections and are electrically connected by the three wires 98, 111, 117 It is preferable to place the signaling,`

mechanisms in the center oit the street intersections and. when this is dono, l prc'tcr to lform a groove in the street surface extending' from one signaling i'nechanism to the other and place the wires 9S. 111, 11'? in said groove. ritter the wires are in place the groove will be filled up with asphalt or other suitable electrical insulating4 material.

The operation oiI the trallic Lignal is as follows: Assiunirgr that all ot' the switches are closed and that the contact ariu 0T .is in the dotted line position in ldigurc El. the motor thii'ounfh the coniiections hereinbei'ore described. will turn the arm contact 0T clockwise in 'Figure tl.

ln the course ot its motion the` arm con tact Gi will engage the contact. titl. therebyv closing' the bell circuit and rinpjingr'lhe bells 112. The ringing` ot the bells is a preliminary wari'nng` to the pedestrians and the drivers of vehicles approaching the lintersections that the semaphore signals are aly .it to ce turned. As the arm contact (5T continues to rotate. it depresifcs the contact 00 so as to permit the contact tl? to pass by the contact 68. As soon as the contact: 0( leaves the Contact 08 the bell-ringing circuit. will be opened and the b s will dirictnitinue ringing. Thi s a warming that the tratlic should stop. There is preeialfly an interval oi" a .second or two between thc time that the contact 07 leaves the contact 0d and the engagement of the Contact 0i' with one oil the arms 73.

rllhe arm 08 now engages one oi the arms 73 and turns said arm. thus cansinol the contact (39 to engage the contact S0 lor a .short interval of time, thus closing the circuit in which are included the motors S. The motors 0 are thus energized and cach operates to wind its chain 10. ldinding` up ot the chain7 as hereinbetore described. causes turning,l of the shaft 23 and with it the semaphore 82, thus signaling to pedestrians and the drivers of vehicles in the street alined edgewise with the semaphore. that theft,`- are to proceed through 'the intersection. and warning the pedestrains and drivers of vehicles in the cross street to stop.

At the end of a predctcrmined interval oit time, for example oneehal't minute, the contact 67 will have made a complete revolution and again engage the contact 0S so that the cycle oiL niovements just described will again occur to first ring' the hell and then cause the semaphore to be given another quarter turn7 thus to indicate a chanac in the iiow of tratiic through the intcrsectimi.

It `the contacts T0, 80 should he closed longer than necessary to cause the sha'tt 23 to be .cgiven a quarter turn. the clutch l2. 13 will slip so that no harm `an come to the mechanism, the slippage occurring' when the slack in the chain 10 between the arin 1f) and the screw 1'? is taken up. lt will. bc understood that, as long as the motor 8 operates, the friction between the clutch members Will be sufficient to hold the arm 19 against being retracted by the spring 2l and that, as soon as the contacts 79, separate, the spring 2l retracts the arm 19 and the pavvl 26 Will slip on the ratchet Wheel 25 so that the shaft 23 will remain in the position to which it has been turned, said shaft being so held by the spring 27. As soon as the arm 19 has thus been retracted, the parts are re-set in position to be operated again when the contact 67 again engages the Contact 68.

If it be desired. to discontinue ringing of the bell at any particular street intersection, the switch 82, 83 will be opened at that par ticular signaling mechanism by operation of the lever 88 into position to move its pivotal connection With the rod into position vertically above the pivot 89.

If a vehicle should run close enough to the housing l to strike one of the projectingl ends of the semaphore 32, said semaphore will turn horizontally on the shaft 23 to permit the vehicle to pass and said semaphore Will then return to the position it was in before the vehicle struck it, as has been described in detail hereinbefore. When the signals are not to be used, for example, in the evening or late at night, the switch 195, 106 will be opened, and then, if desired, the semaphore 32 may be swung in a vertical path into the position shown in dotted lines c in Figure l.

I claim:

l. In aA traffic signal, the combination of a vertical shaft, a semaphore mounted to turn horizontally on said shaft, yielding means for maintaining said semaphore in a given position relatively to the shaft, Ymeans to operate the shaft in one direction, and means in conjunction with a portion of the shaftoperating means to hold said shaft against rotating in the opposite direction when the semaphore is turned in said opposite direction by a moving object striking it.

2. In a traffic signal, the combination of a semaphore, means including a motor to move the semaphore into different positions, an electrically operated audible signal, an electric contact electrically connected with the audible signal, a second electric contact electrically connected with the motor, a third electric contact electrically connected With the motor, a second motor, a contact arm electrically connected With the audible signal and operative by the second motor to intermittently engage the first electric contact, and means intermittently operated by the contact arm to move the third contact into engagement vvith the second contact.

3. In a traffic signal, the combination of a vertical shaft, a semaphore mounted on said shaft, an electric motor, means operative by the motor and including a pawl and ratchet device to turn the shaft in one di# rcction when the motor is energized, means cooperating with a portion of the last means to retract the paivl and ratchet device When the motor is (ile-energized, and means in conjunction With a portion of the pawl and ratchet device yieldingly holding the shaft in the positions to which it is turned.

In a traffic signal, the combination of a vertical shaft, a semaphore mounted on said shaft, an electric motor, a friction clutch driven by said motor, an oscillatory member, a paivl and ratchet connection between the oscillatory member and the shaft, a flexible member adapted to be Wound up by rotation of the loose clutch member to turn the oscillatory member in one direction, and a spring connected with the oscillatory member and operative to turn the oscillatory member in the opposite direction When the motor is cle-energized.

5. In a traffic signal, the combination of an electric motor, a contact arm operative by the motor, an electric contact in the path of travel of the contact arm, a rotative arm in the path of travel of the contact arm, a pair of electric contacts, a motor connected with the last named electric contacts, a rotatably mounted semaphore operated by the motor, an electrically operated auditory signal mounted adjacent the semaphore and electrically connected with the contact arm and first named electric contact, and means operative by the second arm to move one of the last named contacts into engagement With the other of the last named contacts.

6. In a traffic signal, the combination of an electric motor, a rotative contact arm operatively connected with the motor, an electric contact intermittently engaged by the Contact arm as said arm rotates, a second rotative arm intermittently engaged by the vfirst arm at a different time than the electric contact, a pair of electric contacts, a motor connected with the last named electric contacts, a rotatably mounted semaphore operated by the motor, an electrically operated auditory signal mounted adjacent the semaphore and electrically connected with the contact arm and first named electric contact, and means operative by the second arm to move one of the last named contacts into engagement with the other of the last named contacts.

7. In a traffic signal, the combination of a motor, a rotatively mounted cam, an arm projecting from the cam, a spring arm engaged by the cam, an electric contact mounted on the spring arm, a second electric contact adapted to be engaged by the first contact when the cam rotates, a third arm rotatively mounted and operatively connected to the motor, a third electric contact mounted to move `at right angles to the third arm, a motor connected with the last named electric contacts, a rotatably niounted semaphore operated by the inotor, an electrically operated auditory signal mounted'adjacent the semaphore and electrically connected with the contact arm and first named electric Contact, and ineans yieldingly holding the third electric Contact in the path of travel of the third zirin, the first arm being positioned in a plane coincident l0 with the third zirln :1nd cngugezible thereby. Signed at Los Angeles, California this 19th day of July 1921.

JOHN C. BUTTERFIELD. 

